[Elecraft] K3 KIO3 Problem with WSJT-X?

[Joe Subich, W4TV]

> It seems at least possible that the polyphonic audio bleat is being 
> produced by feedback somehow occurring between LIN IN and LIN OUT on
> the KIO3.  Two possibilities - either the sound card has failed in
> this peculiar way, or there is some setting, either in my WIN 10
> computer's sound settings or in the K3's settings, that is causing
> the coupling between LIN IN and LIN out.
Assuming your USB sound device is *NOT* the Windows Default device:

Open the Windows Sound Control Panel, select the USB Sound device,
select recording -> Listen and make sure "Listen to this device"
is *NOT* checked.

Open Windows Sound Control Panel, select the USB Sound device, select
playback -> levels and make sure any "microphone" input is muted.

> If I pull that line from the sound card's LIN IN jack, then the FT8
> audio in the monitor sounds completely normal.

If you pull the line from the sound card's LIN IN jack, there should
be *NO AUDIO*.  Do you have another sound card connected to the mic
input?  Is MENU:MIC+LIN = ON?  Are you using DATA:DATA_A or are you
using USB?

73,

    ... Joe, W4TV


On 2020-06-15 8:37 AM, N4ZR wrote:
> I am trying to diagnose a problem with my K3/KIO3 which surfaced during 
> the ARRL VHF contest.  Previously, I had used this setup for hundreds of 
> QSOs on HF.
> 
> I am using an external Startec USB soundcard.  The KIO3 IN jack is 
> cabled to the speaker output of the soundcard.  The KIO3 OUT jack is 
> cabled to the soundcard's LIN IN jack.  Now here's the problem.  When I 
> transmit with all cables connected, and listen to the monitor on the 
> headphones, I hear a tremendous blast of polyphonic audio so long as the 
> KIO3 OUT line is connected to the soundcard.  If I pull that line from 
> the sound card's LIN IN jack, then the FT8 audio in the monitor sounds 
> completely normal.
> 
> It seems at least possible that the polyphonic audio bleat is being 
> produced by feedback somehow occurring between LIN IN and LIN OUT on the 
> KIO3.  Two possibilities - either the sound card has failed in this 
> peculiar way, or there is some setting, either in my WIN 10 computer's 
> sound settings or in the K3's settings, that is causing the coupling 
> between LIN IN and LIN out.
> 
> Any suggestions gratefully received
>